TAX PLAN RISKS BIG REVENUE LOSS

Asked about a tax increase, President Reagan steamed Tuesday, "There just ain't going to be none." His credo on tax dollars remains that it's better for the Treasury to give than to receive. Thus he insists that tax reform do nothing to reduce huge deficits. Even worse, the White House is trying hard to ignore the fact that its reform plan would make deficits larger still.

Just take a look at the creative bookkeeping that's going on to make the reform look as if it will not increase the deficit. For instance, it makes Jan. 1, 1986, the effective date for ending many tax loopholes, while it doesn't lower tax rates until six months later. There's no economic rationale for the lag -- only the political need to make the reform look neutral toward deficits that it actually increases.

The administration argues that its increase of the deficit would be only minimal -- that during the next five years, this plan would bring in only $12 billion less than would the current tax system. That's correct, as far as it goes. The problem is what happens in the 1990s and beyond. You're not going to find that answer from the administration, though, because the tables in the administration's detailed tax-reform book don't go past 1990. Mum's the word. Asked about the plan's long-term cost, officials say how hard it is to forecast the economy. Nevertheless, there are strong reasons to believe that the Reagan plan would raise far less than the current tax system in future decades.

The White House, for instance, says that a few decades from now the tax on individuals will be 7 percent lower than under the current code and corporate taxes will be 9 percent higher. Well, those changes would balance out if individuals paid about as much tax as businesses do, but that's not the case. Personal income taxes now bring in about four times as much as corporate taxes do. Thus in the long term, the tax cut for individuals will dwarf the increase paid by business. That adds up to a whopping loss of revenue and an explosion of new borrowing.

These revenue losses are worth keeping in mind as Mr. Reagan talks about neutrality and business lobbyists bemoan what a hardship his plan would be. The fact is that unless Congress toughens it, the plan adds up to a tax cut -- a senseless risk no matter how attractive its form.